The Bombay Natural History Society (BNHS) said there has been a 25 per cent increase in flamingo migration since 2019, when 1.2 lakh birds had come visiting. This year, over 1.5 lakh birds were spotted in the first week of April itself.

The society attributed this increase to lower human activity in areas such as Sewri, Thane Creek and the Talawe wetlands, comprising the NRI Complex, Seawoods and TS Chanakya in Navi Mumbai.

These areas would normally see a lot of construction work and human activity but the nationwide lockdown has created ideal conditions for the flamingoes to forage in the wetlands around these places.

Deepak Apte, director of BNHS, said the lockdown has given flamingoes a moment of peace and quiet to roost without disturbance. “Wetland destruction and developmental activities across several areas of the eastern seafront is another reason why larger bird numbers are getting squeezed into smaller pockets like in Navi Mumbai,” he explained.

The spike in the number of migratory flamingoes last year, from the usual 30,000-40,000 to 1.2 lakh, was attributed to an increase in sewage output and industrial runoff, which caused an increase of blue-green algae that these birds feed on.

‘Iconic’ flamingoes

Out of the six flamingo species found in the world, the greater flamingo (taller, with a black-tipped pink bill) and the near-threatened lesser flamingo (shorter, with a dark crimson bill) are found in India.

A BNHS study has found that the number of lesser flamingoes are on the rise in India while the number of greater flamingoes are declining.

Flamingoes are considered iconic in Mumbai. Since the 1980s, flocks of 30,000-40,000 of the bird have been settling along the Thane Creek between September and April.

These birds arrive in the city from the north-west part of India, from Kutch in Gujarat and Sambhar Lake in Rajasthan. A smaller number of the birds are believed to fly in from Pakistan, Afghanistan, Iran and Israel.

The Mumbai Metropolitan Region is said to be the the second-largest flamingo habitat along the west coast after Kutch, according to BNHS, which began its first formal survey of flamingos in the Thane Creek in 2018 as part of a 10-year study of wading birds.